The present disclosure relates to computer devices and particularly to discriminating activity of a computer device user.
Acoustic emanations from computer keyboards have been investigated in the context of computer security threats. It has been recognized that the sound of clicks may differ slightly from key to key although clicks of different keys sound similar to the human ear. Acoustic emanations form a PC keyboard have been investigated, and experiments have shown that processing can be performed to differentiate between key presses of a keyboard. Further it has been shown that typing styles have little impact on a trained neural network's capacity to recognize key presses.